Bring that metronome down, and take your time with it! Get that muscle memory up to speed. Break the solo into bitesize pieces and practice each as segments, then gradually bring them together. You can break parts down to as little as 1 note per segment. Try and recognise phrases as segments.
Analyse the piece a bit, see what techniques you are struggling with, and which techniques you are best at.If you are for example struggling with the ridiculously fast alternate picking section, then work towards Buried Alive's solo as your goal. Practice a few alternate picking exercises to build into it.
Hope this makes sense!